bigblue1, don’t give up yet. With most of the codes gone there are only a couple of possibilities left. Don’t worry about the P1693 code. All this is telling you is there is a trouble code set. Two things can only cause the P0238 code, “Map Sensor Voltage Too High”. Either the MAP sensor is faulty or there is still a poor connection. I am assuming that after clearing the codes the Check Engine Light is on. Is it? When you cleaned the sensor connections (there are 3) could you see any corrosion? It sometimes helps to use a toothpick and dielectric grease to scrape out oxidation.
On my 98, I could only get the lift pump to cycle once with the key on. I believe the early trucks are slightly different from later years. If you can start your engine try loosening one of the two brass plugs on top of the fuel filter with the engine running. Do you see any fuel seeping out? If so your lift pump is running and pumping. Don’t remove the plug or you will be soaked in diesel.
Give me some answers back if you want to follow up. And no I am not a Tech, just too cheap to let others work on my truck.
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Dave
1998 24Valve, BD dual turbo, Mach 4, Smarty, APB, ARP studs, Rickson 19.5s, DPP 4" SS, CON OFE.